Concentration of ores



, ticularly an Patented I .pr. 21, 1931 UNITED STATES PATENT OFFICE FREDERICK G. MOSES, OF NEW YORK, RAYMOND W. HESS, OF BUFFALO, AND ROBERT L.

PERKINS,

OF EAST AURORA, NEW YORK, ASSIGNORS TO THE BARRETT COMPANY,

OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY CONCENTRATION OF ORES No Drawing.

This invention relates to the separation of minerals and the concentration of ores by flotation processes, and is particularly directed to such separation and concentration carried out with the utilization of certain organic sulfur compounds as flotation or mineral collecting agents.

According to the present invention, improved results can be obtained in the separation of minerals and the concentration of ores by carrying out the flotation operation with the addition to the ore or mineral pulp of a tetrahydrothiodiazinethione compound which corresponds with the following probable formula:

i i-nit,

4 a H20 5 2 o=s \s 1 I ore-s where R denotes a hydrocarbon radical, pararyl radical of the benzene series. They may be regarded as derivatives of tetrahydro-l: 3 l-thiodiazine-Q-thion. The phenyl derivative, ordinarily known as N- phenyltetrahydrothiodiaainethione, is of particular interest, and is represented by the following probable formula:

Monro-NH H,o )os The flotation agents of the present invention may be prepared by methods described in the chemical literature.

In carrying out the flotation process, the

flotation agent comprising the tetrahydrothiodiazinethione compound may be incorporatedwith the ore or mineral pulp in any suitable manner or at any suitable time which will insure a satisfactory flotation operation. For example, it may be introduced, in the free state, into the mill in which the ore is being ground, or it may be dissolved, suspended or dispersed in any suitable solvent or dispersing agent as, for example, in one or more of the usual flotation oils or oil mixtures, or in any suitable organic solvent or medium, or in water or in alkali or an alkaline reagent, and the resulting solution, suspension or dispersion incorporat- Application .filed May 20,

19W. Serial No. 193,062.

ed with the ore or mineral pulp. While the agents of the present invention show marked action as flotation or collecting agents in ore concentration, they ordinarily possess insufficient frothing qualities and are therefore generally used to advantage in conjunction with any suitable or well-known frothing agent, e.. g. pine oil, crude turpentine, coal tar acids, etc. They may be also sometimes used to advantage in conjunction with other flotation agents. They may be employed in the pure or purified state; and, in general, they may also be employed in the crude or impure state.

The process of the present invention can be carried out in any suitable apparatus, for example, those of the pneumatic type such as the Oallow cell, or those where the air is incorporated with the mixture by agitation.

ing it to flotation with the flotation agents of the present invention. The alkali may be caustic alkali such as caustic soda, or an alkaline salt such as soda ash, or it 'may be calcium oxide or hydrate.

In the differential minerals, such as zinc blende from associated minerals, the presence of an alkali metal cyanide, or of copper sulfate or other salts, is sometimes advantageous.

The amount of flotation agent required to be used in the -flotation process will vary, it depending partly on the character and composition of the ore, partly on the particular tetrahydrothiodiazinethione .compound employed, and partly on other factors. Ordinarily one-sixth to one-half pound of the flo tation agent per ton of dry ore will be sufficient, but larger or smaller amounts than this may be used.

The invention will be further illustrated by the followin specific example, but it will be-understood t at the invention is not limited thereto. The parts are by Weight.

E wample.-500 parts of a copper sulfide ore (of the Inspiration Copper (30.), assaying 1.34 percent copper, was round in a ball mill with 250 parts of water, 0. 5 parts of hydrated lime (equivalent to 3 pounds per ton of ore), and 0.0625 parts of N-phenyltetrahydrothiodiazinethione (equivalent to one-fourth pound per ton of ore), until practically all of it was sufficiently fine to pass through a 40- mesh screen. The ground pulp was diluted with suflicient water to give a pulp containing about 16 percent solids and subjected to flotation in a J anney mechanical apparatus. The mixture was agitated for minutes during which time about 0.04 parts of pine oil was introduced. 49.7 parts of a concentrate assaying 5.5 percent copper was obtained which is a recovery in the concentrate of8221 percent of the copper. The tailings assayed 0.27 percent copper. It will be noted that the equivalent of about 10 tons of ore was required to give one ton of concentrate.

It will thus be noted that the present invention contemplates the utilization as flotation agents in the separation of minerals and the concentration of ores of tetrahydrothiodiazinethione compounds; thatthe said flotation agents may be incorporated in or with the ore or mineral pulp at any suitable time and in any suitable manner; that they may be used in the free state or in admixture with one another or in solution, suspension or dispersion in any suitable solvent or medium; and that they may be used in conjunction with other flotation agents or with frothing agents, or with both.

The present invention is of more or less general application to thetreatment of different kinds of-mineral substances, both natural, and artificial, by flotation.

Iii will be further understood that the invention is not limited to the use of the particular agents or ingredients mentioned in the example and that other agents, particularly other flotation agents of the class specified, can be similarly used.

e claim:

1. In effecting the separation of minerals,

the process which comprises incorporatingwith the mineral pulp a tetrahydrothio- 'diazinethione compound, and subjecting the resulting mixture'to a froth flotation operation. 2. In effecting the separation of minerals,

the process which comprises incorporating i as with the mineral pulp- 'a I tetrahydrothiodiazinethione corresponding with the probable formula:

H1O N(RP NH C=S oH,-- s where R denotes a hydrocarbon radical, and subjecting the resulting mixture to a froth flotation operation. 3. In effecting the separation of minerals, the process which comprises incorporating with the mineral pulp a tetrahydrothiodiazinethione body corresponding with the probable formula where R signifies an aryl group,'and subjectv where R denotes an aryl group of the hen zene series, and subjecting the resulting mixture to a froth flotation operation.

5. In effecting the separation of minerals, the process WlllCh comprises incorporating N -phenyltetrahydrothiodiazinethione with the mineral pulp, and subjecting the resulting mixture to a froth flotation operation. I

6. In effecting the concentration ofa copper sulfide ore, the process which comprises subjecting a pulp of the ore to a froth flotation operation in the presence of a tetrahydrothiodiazinethione.

7. In effecting the concentration of a copper sulfide ore, the process which comprises subjecting a pulp of the ore to a froth flotation operation in the presence of a tetrahydrothiodiazinethione having the following probable formula:

N(R)--NH om--s wherein R stands for a hydrocarbon radical.

8. In effecting .theconcentration of a copper sulfide ore, subjecting a pulp of the ore to a froth flotation operation tetrahydrothiodiazinethione.

In testimony whereof we aflix our signathe process which comprisesloa in the presence of N -phenyl- 

